Infectious diseases remain a constant threat since old ages. Different viruses emerged from time to time and devastated the civilizations. The emergence of new microbes and pathogens also posed a major risk to food safety and food security. New viruses emerge from existing viruses by getting changes in the genome through mutation. Mutations are attained by viruses through phenomena of antigenic shift and antigenic drift during genetic re-assortment in virus replication. The emergence of hyper-virulent viruses results in sudden and unexpected disease outbreaks in human and animal populations. The prevailing prophylactic measures of immunization against mutant viruses failed due to variations in the antigenicity of mutated virus strains.
Adeno viruses are a group of diverse viruses which affect a wide range of mammalian species including humans as well as domesticated and wild avian species. Virus classes that infect avian species are known as Aviadenovirus. Aviadenovirus are responsible for avian diseases of inclusion body hepatitis, hydropericardium syndrome and gizzard erosions. Siadenovirus cause diseases in turkeys and pheasants while Atadenovirus produce disease in layer poultry.
Aviadenovirus has five classes and 12 strains having individually distinct disease capabilities. Avian adenovirus got its first recognition during 1963 in the USA and in Pakistan during 1987 by devastating the poultry industry of Pakistan. Currently, adenovirus is causing field outbreaks of inclusion body hepatitis in commercial poultry with high economic losses. Losses to the poultry industry of Pakistan by these viruses are estimated at 80 million rupees annually. This contributes negatively to the availability of per capita required animal origin protein to the rapidly growing human population of Pakistan. This results in nutritional deficiencies in children and adults as well as uneven food supplies. At the national level, the ratio of beef and mutton production to the meat pool have constant production or decreasing tendencies. Hence, the poultry industry is playing a vital role to bridge the gap. Pakistan poultry industry has an annual turnover of 750 million rupees with a 10% annual growth rate.
Though the avian adenoviruses are not zoonotic in nature and rearing of adenovirus free flocks contributes to the production of healthy chicken meat. Environmental factors and animal diseases impose their impact on human health and wellbeing and are the key to one health concept. These viruses can be controlled through bio-security measures and immunization. The new concept of vaccines production is of recombinant vaccines which are safer and more reliable, also nullifies the probability of reversion of vaccinal strains of the virus to the pathogenic ones.
Prevention and control measures against pathogens are the need of the hour to build a healthy nation. The study was concluded in collaboration with eminent scientists, Prof. Dr. M. Yasin Tipu, Dr.Raheela Akhtar and Dr. Arfan Ahmad.
HAFIZ MUHAMMAD ANWAR-UL-HAQ
LAHORE
